SOUTH BEND, Ind. (AP) - Tested like never before, Matt Leinart, Reggie Bush and Southern Cal showed they have a championship jaw to go along with all that talent.

Leinart pushed and spun his way into the end zone with 3 seconds left to cap a chaotic finish and No. 1 USC escaped with its 28th straight victory, a back-and-forth 34-31 win Saturday over No. 9 Notre Dame in a game that lived up to the hype.

For a moment the Irish (4-2), dressed for success in kelly green jerseys, thought they had added another stunning upset to their illustrious history. Leinart scrambled from inside the 5, launched himself toward the end zone but was stopped short and the ball was sent flying out of bounds.

With the clock ticking down to 0:00, Notre Dame's fans rushed the field and coach Charlie Weis raised his hands in victory. But USC coach Pete Carroll sprinted down the sideline to plead his case. The officials huddled, then put 7 seconds back on the clock and the ball inside the 1.

The Heisman Trophy winner had the option to spike the ball to regroup his team or go with what he had. He chose the latter, took it in himself over the left side and got a little help moving the pile from Bush.

"I used all 200 pounds of my body to push Matt in," said Bush, who ran for 160 yards on 15 carries with three touchdowns.

Carroll said USC (6-0) never even considered settling for a field goal attempt to send it to overtime.

Irish quarterback Brady Quinn had given Notre Dame a 31-28 lead with 2:02 left, dashing around right end for a 5-yard touchdown, extending his right arm across the goal line with the ball.

But Leinart wasn't done. He completed a 61-yard pass to Dwayne Jarrett on a fourth-and-9 at his own 26 and a few plays later called his own number for the winner.

"I just saw it, I thought it was there and I just wanted to get in," Leinart said. "I didn't want to spike the ball so I made the choice and they were looking down from up above and we got in. That was all that mattered."

He sat on the bench after his score, helmet still on, looking exhausted and waiting for a final kickoff that Notre Dame couldn't turn into a miracle.

Bush ran for 160 yards and three touchdowns for the two-time defending champions.

Weis tapped into the Fighting Irish's storied past and even in defeat etched a spot in it for himself and his team. He broke out all the stops, bringing in "Rudy" and Joe Montana to fire up his team and the fans in Friday night's pep rally, then sent the Irish off in good-luck green after warm-ups on Saturday.

The Trojans trailed at the half for the third time this season, this time by 21-14 after Tom Zbikowski's 60-yard punt return early in the second quarter gave the Irish their first lead.

But Bush tied the game with a 45-yard scoring gallop early in the third. His second long TD of the game put him over 100 yards rushing for the fifth straight game.

Notre Dame got the lead back with a field goal, then D.J. Fitzpatrick missed from 34 yards when the Irish could have gone up by six.

Bush struck again, going around the corner from 9 yards out with about five minutes left to make it 28-24.

Then it was Quinn's turn to have a Heisman moment.

He guided the Irish on an 87-yard drive, completing all three of his passes and finally putting Notre Dame up with 2:02 left.

Quinn finished 19-for-35 for 264 yards.

USC came in averaging 51 points per game, but the Irish put pressure on Leinart and intercepted him twice, the first time since the final game of the 2003 regular season he tossed two picks.

The dynamic backfield of LenDale White and Bush was turned into a solo act, as Bush kept USC in it until Leinart made the plays of the game.

He threw a prefect fade over a defensive back to Jarrett on the huge fourth-down conversion and finished with 301 yards passing.

For a while though, Notre Dame looked ready to add the Trojans to its list of historic streak stopping upsets.

It was Notre Dame that stopped the longest winning streak in NCAA history when the Irish beat Oklahoma and ended its 47-game romp in 1957.

In '46, Army had won 25 straight when Notre Dame tied the Black Knights, and Texas had won 30 in a row before losing to the Irish in 1971.

Two years later, USC had a 23-game winning streak end in the shadows of Notre Dame's Golden Dome.

On Saturday, USC was too tough, too resilient, to let it happen, and the Trojans are still on track to three-peat.

On a cloudless, windy, sweatshirt kind of day, USC struck first in familiar fashion - turning a takeaway into points.

Keith Rivers picked off Quinn's tipped pass and two plays later Bush burst through the line and hurdled a tackler on the way to a 36-yard touchdown.

Notre Dame responded with a long drive aided by consecutive 15-yard penalties by USC, and Travis Thomas finished it with a 16-yard touchdown.

Another quick-strike drive by USC resulted in White's 3-yard TD run, but Notre Dame controlled the rest of the half and had everyone believing the Fighting Irish could again beat the behemoth and reshape the national title race.